Stochastic Schrödinger equation for hot-carrier dynamics in plasmonic systems

Area of Science:

• Computational chemistry
• Quantum mechanics
• Materials science

Background:

• Hot-carrier dynamics in photoexcited plasmonic systems are crucial for applications like CO2 photoreduction.
• Understanding the interplay between quantum and classical effects is essential for designing efficient photocatalysts.

Purpose of the Study:

• To develop and apply a multiscale computational method for studying hot-carrier dynamics.
• To investigate the influence of relaxation (T1) and dephasing (T2) times on charge dynamics.
• To elucidate the role of a metallic nanoparticle in plasmon-driven photoreduction.

Main Methods:

• Coupling open quantum systems theory with real-time ab initio electronic structure calculations.
• Utilizing the Markovian Stochastic Schrödinger equation and ab initio GW/Bethe-Salpeter (BSE) equation.
• Modeling the metallic nanoparticle classically using the polarizable continuum model.

Main Results:

• Observed net hole injection from rhodium to a CHO fragment, enhanced by two orders of magnitude due to the nanocube.
• Demonstrated that nonradiative decay (T1) rapidly decreases charge population.
• Showed that pure dephasing (T2) erases coherent charge injection dynamics.

Conclusions:

• The multiscale method accurately captures hot-carrier dynamics in photoexcited plasmonic systems.
• Metallic nanoparticles significantly enhance charge generation in plasmon-driven reactions.
• Both relaxation and dephasing times play critical roles in controlling charge dynamics and photoreduction efficiency.